Shoplifting of merchandise displayed in stores is a continuing problem. Shoplifting of jewelry is particularly hard to detect because of the small size of the jewelry. One obvious solution is to put the jewelry in a locked showcase and to have a salesperson unlock the showcase and supervise shoppers' inspection of the merchandise. However, that has been found to reduce sales and it increases the number of salespersons required.
Other solutions to the problem involve firmly mounting jewelry on cards and displaying the cards on units that lock the cards in place but allow shoppers to inspect the jewelry. The units are unlocked to release the cards. Such devices are shown in U.S. Pat. Nos. 4,026,417 and 4,155,457. For other kinds of merchandise, display devices having rotating members that in one position allow removal of merchandise and in a second position prevent removal are shown in U.S. Pat. Nos. 646,388, 3,674,156, 3,924,749, 3,938,665, and 3,960,273. U.S. Pat. No. 164,114 discloses a paint exhibitor having a plurality of vertically rotatable panels disposed between rigid pillars.
None of those display units allows addition of fresh merchandise when the unit is in the locked position; all must first be unlocked. Each of the two jewelry display units requires substantial space to display a given amount of merchandise. If a unit is on top of a showcase, shoppers are hindered in viewing the goods in the showcase. Furthermore, in those units the means used to restrain the jewelry display cards are clearly visible, which is undesirable for aesthetic and psychological reasons.